Cisco ONS 15454 MSTP Release 9.2.1 extends the overall data bandwidth that the system can transport by a factor of four, allowing transmission across Cisco ONS 15454 MSTP dense wavelength-division multiplexing (DWDM) for up to 320 channels at 10 Gbps over 80 wavelengths at 40 Gbps.

The bandwidth carried on core and metropolitan (metro) DWDM networks is growing exponentially, but operators’ revenues are not growing as quickly. The Cisco ONS 15454 40 Gbps solution can dramatically lower the cost to carry bandwidth, helping maintain and improve customers’ profitability. Internet growth is still exponential, mainly because of demand for next-generation services such as quadruple play (data, voice, video, and mobility), video distribution, Internet Protocol Television (IPTV), and other high-bandwidth services.

This growth in data transmission in DWDM networks that require technology advances to support such large bandwidth. Scaling from 10 to 40 Gbps is the perfect solution for this problem; it quadruples the bandwidth that can be transported over existing fiber networks.

●40-Gbps signals must work in fully uncompensated networks up to more than 2000 km.

●40-Gbps signals must work with very low-quality fiber with very high polarization mode dispersion (PMD) coefficients.

●40-Gbps technology must work on 50-GHz systems with negligible filtering penalty.

●40-Gbps units must fit mechanically and thermally with existing installed shelves with no effect on existing units, allowing full back-compatibility and no restriction rules for where the units can be placed.

Each client interface provides a multiservice (OC-192/STM-64/10GE LAN/10GE WAN/8G FC/10G FC/OTU2) interface through a 10-Gbps Small Form-Factor Pluggable (XFP) optics module with LC connectors, providing the flexibility to support several optical reaches with support for qualified XFP modules. The muxponder card supports any mixture of XFP reach types and also supports in-service insertion or removal without affecting other active ports, allowing superior networking flexibility and reduced preplanning activities.

You can use various types of XFP Pluggables depending on the reach and application needed (Table 1).

The DWDM line interface provides a configurable 43.018-Gbps/44.570-Gbps G.709 OTU3 digital wrapper, long-reach/long-haul, ITU-compliant, 50-GHz spaced optical interface using LC connectors supporting G.709 OTU3 digital-wrapper interfaces. The DWDM output line interface is tuneable across the full optical C band, dramatically reducing inventories for spares. When operated within the outlined specifications, each card can transport each of the 10-Gbps signals with a maximum bit error rate (BER) of 10E-15.

The muxponder card incorporates the four clients and one DWDM line interface on the same card. The muxponder cards are deployable in any of the 12 multiservice interface card slots of the Cisco ONS 15454 platform, in systems with or without cross-connect cards. The addition of a cross-connect card allows the platform to support hybrid applications, containing transparent 10-Gbps services as well as aggregation of the other services supported by the Cisco ONS 15454 platform. The only other common card required for operation is the timing, communications, and control (TCC) card.

The trunk port supports FEC and EFEC, and you cannot disable such mechanisms. The output bit rate does not depend on the selected algorithm, but you can provision the error coding performance.

●FEC: Standard G.975 Reed-Salomon algorithm

●EFEC: Standard G.975.1 (Subclause I.7 ); two orthogonally concatenated BCH super FEC code. This FEC scheme contains three parameterizations of the same scheme of two orthogonally interleaved block codes (BCH). The constructed code is decoded iteratively to achieve the expected performance. EFEC provides 2 dB more reach than standard FEC. You can enable this EFEC algorithm in three of the four client ports (port 1 does not support E-FEC). Two different Over-Heads are applied if the trunk is OTU3 or OTU3 overclocked trunk (OTU3e): 10 percent for OTU3e mode and 13 percent for OTU3 mode.

Client ports, pending the support of FEC rate on the pluggable, support a FEC mechanism that can be disabled:

The CP-DQPSK modulation scheme consists of multiplexing two DQPSK signals over two different orthogonal polarizations, as shown in Figures 3 and 4.

Figure 3. CP-DQPSK Tx Domain Scheme and Transmitter Scheme

Figure 4. CP-DQPSK Transmitter Scheme

The core of the 40-Gbps CP-DQPSK modulation scheme is the receiver that is based on coherent detection, where a digital signal processor (DSP) calculates the inverse of the optical system matrix, allowing the receiver to recover the original transmitted signals (Figure 5).

●Very good spectral density that allows traffic to cross a long cascade of reconfigurable optical add-drop multiplexers (ROADMs) with negligible penalty

Provisionable Differential Mode

CP-DQPSK shows the best absolute performance, but it is sensitive to the presence of other 10-Gbps signals because the nonreturn to zero (NRZ) signals create an XPhase effect over the phase-sensitive CP-DQPSK signal. This situation encourages the creation of a guard band, an unused region between 10- and 40-Gbps signals that can potentially cause a major limitation in optical mesh networks. Cisco allows you to use a simple software configuration to reduce or delete the guard band to configure the card in differential mode, which is intrinsically much more robust than the 10-Gbps intercorrelation effect.

Muxponder Card Versions

Two versions of the Cisco 40-Gbps Full-Band Tuneable CP-DQPSK Muxponders are offered to support different application requirements:

The card can be provisioned in two operational modes: OTU3 or OTU3e. In OTU3 mode, the card can transparently multiplex any mix of STM-64/OC-192, 10GE LAN, 10GE WAN, OTU2, or 8G FC signals. In OTU3e mode, you can combine any mix of 10G FC and OTU2e (G,Sup43 7.1) signals, as shown in Table 2.

Table 2.Muxponder Client Configurations and Mapping

Client Format

Frequency (GHz)

Mapping

Trunk Format

Frequency (GHz) with FEC

Frequency (GHz) with EFEC

8G-FC

8.500

Enhanced OTN mapping (proprietary)

OTU3

43.018

45.548

OC192/STM64/10GeWAN-PHY

9.953

ODTU23 multiplexing

10GE LAN-phy

10.312

GFP-F (G.SUP43 7.3) or LAN-WAN (G.SUP43 6.1)

OTU2 (OC192/STM64/10GeWAN-PHY)

10.709

ODTU23 multiplexing

10G-FC

10.519

512/513 transcoding plus GFP-T

OTU3e

44.570

45.794

OTU2e (10Ge LAN-PHY)

11.096

ODTU23 multiplexing (G.SUP43 7.1)

The card also can process provisionable SONET/SDH overhead bytes. It is possible to pass the bytes transparently or to terminate the line and section overhead. In transparent mode, client terminal equipment interconnected over a muxponder-based circuit can communicate over the section (or multiplexer section) data communications channel (SDCC/MSDCC), can signal 1+1 and bidirectional line switched ring or multiplex section-shared protection ring (BLSR/MS-SPR) protection switching using the K1 and K2 bytes, and can support provisionable section trace capabilities over the J0 byte. In addition, the muxponder circuit, whether provisioned in transparent or terminating mode, can support client circuits based on unidirectional-path switched ring (UPSR) or subnetwork connection protection (SNCP).

Full transparency is provided by the enhanced multiplex engine that performs the multiplexing of the incoming 10-Gbps signals at the optical transport network (OTN) layer that are no longer in the SONET/SDH domain. Different mapping schemes are used pending the payload to guarantee full transparency of the signal, as indicated in Table 2.

The 10GE LAN PHY-to-WAN PHY conversion is implemented according to the standard defined in IEEE 802.3: WIS (WAN interface sublayer). The 10GE LAN PHY interfaces have an effective line rate of 10.3125 Gbps (10 Gbps of data traffic encoded in a 64B/66B protocol). The 10GE WAN PHY interfaces conform to the SONET/SDH standards to achieve 9.95328 Gbps and allow service providers to use their existing SONET/SDH Layer 1 infrastructure.

WAN PHY is used to transport 10 Gigabit Ethernet across SDH/SONET or WDM systems without having to directly map the Ethernet frames into SDH/SONET first. The WAN PHY variants correspond at the physical layer to 10GBASE-SR, 10GBASE-LR, 10GBASE-ER, and 10GBASE-ZR, respectively, and hence use the same types of fiber and support the same distances.

Wavelength Tuneability

The muxponder cards operate on the 50-GHz ITU grid and are tuneable across 82 adjacent 50-GHz channels for the C-band module and across 80 adjacent 50-GHz channels for the L-band module. The incorporation of tuneability into the muxponder cards reduces the customer’s inventory required to cover all of the wavelengths for deployment and spares. Tuneability is software-provisionable.

Flexible Protection Mechanism Support

You can deploy the muxponder card, depending on your network requirements, to support the many protection mechanisms found in optical transport networks. Table 3 outlines the supported protection options that help deliver the service-level agreements (SLAs) that the application requires.

Table 3.Protection Formats

Protection Type

Capabilities

Unprotected

There is no client terminal interface, muxponder card, or DWDM line protection. The client signal is transported over a single unprotected muxponder card.

Similar to unprotected format, protection is provided through client line or path protection through transparent signal transport through a muxponder circuit.

Y-cable protection

This protection provides muxponder card and DWDM line protection without requiring client terminal equipment interface protection. It uses a Y-protection device to optically split a single client interface into two muxponder cards. The Cisco ONS 15454 system controls the muxponder card active or standby status to provide a single signal feed to client equipment.

The Cisco 40-Gbps Full-Band Tuneable CP-DQPSK Muxponder Card times the client side and the DWDM line optical transmitter port with the clock derivate by the shelf processor. The Cisco ONS 15454 platform provides the option to recover timing signals for node-timing reference, with synchronization status messaging support, from any of the four client optical interfaces in case of SONET/SDH, Ethernet, and OTN signal, in addition to the standard options of using an external clock derived from a Building Integrated Timing Supply (BITS) clock or another optical interface card on the Cisco ONS 15454 system. The muxponder card can also recover the clock from the trunk when the operational mode is OTU3. In addition, the muxponder card can maintain synchronization from an internal clock even if both the shelf processors (active and standby) fail.

●Up to six muxponder cards per shelf assembly and up to 96 10-Gbps interfaces per bay frame

Flexible restoration options

●Transparent support for UPSR/SNCP, BLSR/MSP, and 1 + 1 APS/MSP

●Client Y-protection

●OCH-trail protection through PSM

●Unprotected (0 + 1)

Management

The Cisco ONS 15454 MSTP provides comprehensive management capabilities for operations, administration, monitoring, and provisioning (OAM&P) accessed through the integrated Cisco Transport Controller craft interface with support from the Cisco Transport Manager element management system The muxponder card incorporates provisionable digital-wrapper (G.709) functions, providing DWDM wavelength performance-management capabilities, especially for services transported transparently across the network. Without the digital-wrapper function, a carrier transporting a service transparently would be unable to identify network impairments that may degrade the transported signal and exceed SLA requirements. The generic communication channel (GCC) of the digital wrapper provides a separate communications channel, other than the SDCC or regenerator SDCC (RSDCC) in SONET/SDH signals, to be used by the platform when transparent signals are transported. This GCC allowss the Cisco ONS 15454 system to extend its advanced network autodiscovery capabilities to DWDM-based services. The integrated Cisco Transport Controller craft manager and the Cisco Transport Manager offer you OAM&P access for the system.

Far-End-Laser-Off Behavior

The Cisco 40-Gbps Full-Band Tuneable CP-DQPSK Muxponder can provision the far-end-laser-off behavior for ONSET/SDH payloads. You can use the Cisco Transport Controller to configure how the remote client interface behaves following a fault condition. You can configure the remote client to squelch or to send an alarm indication signal (AIS).

For data signals (10GE, 10G FC, or 8G FC) the behavior is squelching.

Performance Monitoring

The performance-monitoring capabilities of the muxponder card support both transparent and nontransparent signal transport. For SONET/SDH signals, standard performance monitoring, threshold-crossing conditions, and alarms are supported per Telcordia GR-253, GR-474, and GR‑2918; ITU G.828; and ETS 300 417-1 standards. Each digital-wrapper channel is monitored per G.709 (OTN), G.8021. Optical parameters on the client and DWDM line interfaces support loss of signal (LOS), laser bias current, transmit optical power, and receive optical power. Calculation and accumulation of the performance-monitoring data are in 15-minute and 24-hour intervals as per G.7710. Ethernet data is monitored using Remote Monitoring (RMON).

A detailed list of performance monitors is given in Table 9.

The muxponder card incorporates faceplate-mounted LEDs to provide a quick visual check of the operational status of the card. An orange circle is printed on the faceplate, indicating the shelf slot in which you can install the card.

Regenerator Configuration

The Cisco 40-Gbps Full-Band Tuneable CP-DQPSK Muxponder also supports the OTU3 regeneration function. You can configure two cards to work in unidirectional mode, allowing the muxponder to perform the OTN O-E-O regeneration function as depicted in Figure 6.

The continued proliferation of data-intensive enterprise services (virtual offices and related services such as video conferencing, and VPNs) and mass-market deployment of high-end consumer applications (such as high-definition video on demand [VOD] and IPTV) are driving transmission speed through the 10-Gbps–based DWDM transport network. The Cisco 40-Gbps solution aims to quadruple the available fiber transport bandwidth with performance comparable to the 10-Gbps solution.

Fiber relief is one of the primary applications for the Cisco 40-Gbps muxponder solution. Bandwidth transport demand increased in the last 3 years, consuming existing 10-Gbps-wavelength-based DWDM systems. With the 40-Gbps muxponder, it is possible to significantly increase existing DWDM system capacity. With the 40-Gbps Muxponder, Cisco can upgrade an existing 80-channel 10-Gbps network equipped with 64 wavelengths with an additional 16 wavelengths at 40 Gbps that carry an additional 64 10-Gbps signals. The Cisco solution was designed specifically to cope with existing 10-Gbps channels without any need to upgrade the existing optical infrastacture.

Industry trends show that the adoption of 8-Gbps Fibre Channel is becoming a necessity in data center environments because of the increase of storage area network (SAN) services such as server virtualization. The 40-Gbps muxponder offers a hyperdense 8-Gbps Fibre Channel solution, allowing you to transmit up to 320 8-Gbps Fibre Channel signals over a single fiber pair over the C-band (Figure 7).

The LAN-WAN conversion on the Cisco 40-Gbps Full-Band Tuneable CP-DQPSK Muxponder allows service flexibility to handle existing SONET/SDH OC-192/STM-64 facilities that are mapped for 10 Gigabit Ethernet payloads. Important applications include the transport of 10 Gigabit Ethernet over traditional SONET/SDH networks and submarine landing-side translation where a vast majority of the systems are based only on time-division multiplexing (TDM).

Note that all compliance documentation may not be completed at the time of product release. Please check with your Cisco sales representative for countries other than Canada, the United States, and the European Union.

1 Short-term refers to a period of not more than 96 consecutive hours and a total of not more than 15 days in 1 year (a total of 360 hours in any given year, but no more than 15 occurrences during that 1-year period). The values shown are valid for M6 or M2 chassis. M12 chassis will support 55º C only in case ONS-XC-10G-S1= SFP is used. If a different SFP model is used, maximum allowed temperature for M12 is 50º C.